JP2005307976A - Method for providing hydraulic pressure from engine lubricating system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve efficiency of whole engine lubricating system. <P>SOLUTION: This method includes a process for supplying oil from a variable displacement pump 6 to an engine lubrication gallery for lubricating an engine, a process supplying oil from the variable displacement pump 6 to engine accessories 10, 14 having variable oil demands and having pressure regulators 12, 16 respectively, a process for adjusting output of the variable displacement pump 4 to sum of fluid required by the engine lubricating system and fluid demand created by the pressure regulators 12, 16, and a process for supplying oil from the variable displacement pump 6 to an accumulator 48 to accumulate accumulator hydraulic pressure for use in mechanical work later. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to the field of engine lubrication systems. More particularly, the present invention relates to a method for providing hydraulic pressure from an engine lubrication system for mechanical work.

  Conventionally, automotive accessories such as cooling fans, power steering systems, A / C compressors, engine coolant pumps, superchargers and alternators are provided separately and of constant (ie fixed) volume driven by the engine. It is operated using a pump or is operated by a direct drive. However, the individual driving forces required by the accessories are not well adapted to the engine speed.

  The solutions for driving force allocation by auxiliary machines are described in US Pat. No. 3,952,509, US Pat. No. 4,420,937, US Pat. No. 4,819,430, US Pat. No. 5,800,131 and US Pat. No. 6,644,025.

  In U.S. Pat. No. 3,952,509, a variable displacement pump supplies working fluid to a continuous and intermittent hydraulic circuit. The continuous circuit supplies pressure for power steering of the tractor, and the intermittent circuit supplies pressure for driving the hydraulic ram, for example, moving the auger up and down.

  The first flow divider provides constant pressure to the continuous hydraulic circuit. The second flow divider provides pressure when any hydraulic cylinder of the intermittent hydraulic circuit is being driven. The load on the system is for hydraulic pistons, not for continuous flow devices such as motors. The system does not provide lubrication to the engine.

  U.S. Pat. No. 4,420,937 discloses a system in which the volume of the variable volume pump in the hydraulic circuit is minimized when the actuators in the system are not operating. The circuit includes a flow sensor that detects the dynamic pressure of the fluid, and can change the static pressure into the dynamic pressure.

  U.S. Pat. No. 4,819,430 discloses a working fluid circuit that is divided into two circuits, a first circuit and a second circuit. The variable displacement pump is the fluid source for the first circuit that regulates the steering system.

  The second circuit is controlled by a fixed capacity pump. A valve that reacts to the demand between the first circuit and the second circuit increases the discharge rate from the fixed pump to the first circuit in proportion to the discharge rate of the variable displacement pump.

  U.S. Pat. No. 5,800,131 discloses a variable displacement pump that regulates engine lubricant flow based on engine parameters. Hydraulic pressure is used to move the piston.

U.S. Pat. No. 6,644,025 discloses a controller for supplying pressurized working fluid to at least two hydraulic devices. The controller has a variable displacement pump that is controlled depending on the required fluid flow, settings and pressure compensator. The controller uses a pressure compensator to prevent excessive flow of working fluid to the hydraulic device by allowing only one valve device to draw control pressure from the supply pressure.
U.S. Pat.No. 3,952,509 U.S. Pat.No. 4,420,937 U.S. Pat.No. 4,819,430 U.S. Pat.No. 5,800,131 U.S. Patent 6,644,025 US patent specifications

In the above conventional method, the requirement of the engine accessory is combined with the requirement of engine lubrication, and the variable displacement pump is adjusted based on the amount of fluid required by the engine lubrication system and the amount of fluid required by the engine accessory. None were configured, and none were configured to provide immediate fluid power when required. For this reason, the conventional system is not very efficient in the entire system related to the circuit.
The present invention has been made in view of such a conventional situation, and intends to provide a method capable of improving the efficiency of the entire engine lubrication system.

The invention of claim 1 is a method for providing hydraulic pressure from an engine lubrication system for mechanical work in an internal combustion engine, and comprises the following steps.
a) supplying oil from the variable displacement pump to the engine lubrication gallery to lubricate the engine.
b) supplying oil from the variable displacement pump to at least one engine accessory having variable oil requirements and each having a pressure regulator;
c) adjusting the discharge volume of the variable displacement pump to the total fluid demand required by the engine lubrication system and the fluid demand generated by the pressure regulator.
d) supplying oil from the variable displacement pump to the accumulator to accumulate accumulator hydraulic pressure for later use as mechanical work.

In the invention of claim 2, at least one engine accessory is
a) Cooling fan driven by hydraulic motor b) Power steering system c) Air conditioner compressor driven by hydraulic motor d) Engine coolant pump driven by hydraulic motor e) Alternator driven by hydraulic motor f) Supercharger driven by hydraulic motor g) Electrohydraulic valve drive system h) Selected from the group of suspension drive motors.

  In the invention of claim 3, the flow of oil for lubricating the engine is based on engine parameters.

  The invention of claim 4 further includes a step of using accumulator hydraulic pressure to operate at least one engine accessory.

  The invention of claim 5 further includes the step of using accumulator hydraulic pressure via a variable displacement pump to add work to the crankshaft driven by the engine.

  The invention of claim 6 further includes a step of supplying oil from the fixed displacement pump to the engine lubrication gallery in order to lubricate the engine, and the variable displacement pump is configured to satisfy the requirements of the engine and supply of the fixed displacement pump. Supply enough oil to make up the difference.

  The invention of claim 7 is a hydraulic pressure demand engine accessory drive system for an internal combustion engine, comprising a variable displacement pump having a pump fluid communication input from an oil sump and a pump fluid communication output to a high pressure manifold, and variable A variable displacement pump controller attached to the displacement pump and in communication with the ECU; an engine having an engine fluid communication input from the high pressure manifold and an engine fluid communication output to the oil sump; a variable oil demand and pressure regulator; And a regulator having at least one engine accessory having a regulator input from the high pressure manifold and a regulator output to the sump, wherein the pump fluid communication output is independent of the engine output and at least one engine accessory. Based on the total amount of fluid required by the pressure regulator There have been adjusted by the variable displacement pump controller.

  The present invention further includes an accumulator having a fluid communication line to a high pressure manifold for storing and supplying energy as an accumulator hydraulic pressure.

  In the invention of claim 9, the ECU controls whether the accumulator receives the oil, maintains the oil, or supplies the oil.

  In the invention of claim 10, the accumulator hydraulic pressure operates at least one auxiliary machine.

  In the invention of claim 11, the accumulator hydraulic pressure adds work to the engine driven crankshaft via the variable displacement pump.

  In the invention of claim 12, the variable displacement pump is replaced with an electric starter motor used to start the engine.

  In the invention of claim 13, the high pressure manifold operates the pressure regulator.

  In the invention of claim 14, the ECU monitors the sensor of the engine.

  In the invention of claim 15, the sensor monitors the temperature and the rotational speed of the engine.

In the invention of claim 16, at least one engine accessory is
a) Cooling fan driven by hydraulic motor b) Power steering system c) Air conditioner compressor driven by hydraulic motor d) Engine coolant pump driven by hydraulic motor e) Alternator driven by hydraulic motor f) Supercharger driven by hydraulic motor g) Electrohydraulic valve drive system h) Selected from the group of suspension drive motors.

  In the invention of claim 17, an oil cooler is further provided at the regulator output to the oil sump of at least one engine accessory.

  The invention of claim 18 further includes a fixed displacement pump having a fixed pump fluid communication input from the sump and a fixed pump fluid communication output to the engine lubrication gallery for engine lubrication.

  In the nineteenth aspect of the invention, the variable displacement pump supplies only enough oil to compensate for the difference between the engine demand and the fixed displacement pump supply.

  The method according to the present invention provides hydraulic pressure from an engine lubrication system for mechanical work in an internal combustion engine by supplying oil to an engine lubrication gallery and at least one variable oil demand accessory to lubricate the engine. To do. Each of the variable oil demanding auxiliary machines has a pressure regulator.

  Regardless of engine output, the displacement of the variable displacement pump is adjusted based on the total amount of fluid required by the engine lubrication system and engine accessories. Fluid requirements are determined by the individual pressure regulators of each engine accessory. In a preferred embodiment, the accumulator stores a high pressure fluid that is used to operate the hydraulic accessory.

  A method of providing hydraulic pressure for mechanical work from an engine lubrication system of an internal combustion engine includes supplying oil from a variable displacement pump to an engine lubrication gallery to lubricate the engine. The method further comprises supplying oil from a variable displacement pump to at least one engine accessory having variable oil requirements and each having a pressure regulator.

  The method further comprises adjusting the displacement of the variable displacement pump to the total amount of fluid required by the engine lubrication system and the fluid demand generated by the pressure regulator. The method further comprises the step of supplying oil from the variable displacement pump to the accumulator to accumulate the accumulator hydraulic pressure for later use as mechanical work.

  In a preferred embodiment, the engine accessory is a hydraulic motor driven cooling fan, a power steering system, a hydraulic motor driven air conditioner compressor, a hydraulic motor driven engine coolant pump, a hydraulic motor driven alternator, a hydraulic motor driven. Supercharger, electro-hydraulic valve drive system, or suspension drive motor.

  The fluid flow for lubricating the engine is preferably based on engine parameters. A method according to another embodiment of the invention includes the step of using the hydraulic pressure of the accumulator to operate at least one hydraulic auxiliary machine. A method according to yet another embodiment of the present invention includes the step of using accumulator hydraulic pressure via a variable displacement pump to provide work to the crankshaft of the engine.

  An engine accessory drive system for an internal combustion engine with hydraulic demands has a variable displacement pump having a pump fluid communication input from an oil sump and a pump fluid communication output to a high pressure manifold. The system further includes a variable displacement pump controller attached to the variable displacement pump and in communication with the ECU.

  The system further has an engine fluid communication input from the high pressure manifold and an engine fluid communication output to the sump. The system further includes at least one engine accessory having a variable oil demand and a pressure regulator. In this case, the pressure regulator is in fluid communication and has a regulator input from the high pressure manifold and a regulator output to the oil sump.

  The system further includes a fluid communication line to the high pressure manifold for storing and supplying energy as an accumulator fluid pressure. The pump fluid communication output is regulated by a variable displacement pump controller by a pressure regulator of at least one engine accessory and based on the total amount of fluid required by the engine for lubrication.

  The high pressure manifold preferably operates a pressure regulator. The ECU preferably monitors an engine sensor. The sensor preferably monitors engine temperature and speed. The system according to one embodiment of the present invention further includes an oil cooler in the regulator output to the oil sump of at least one engine accessory.

  The ECU preferably controls whether the accumulator receives oil, holds oil or supplies oil. The hydraulic pressure of the accumulator is preferably driving at least one hydraulic accessory.

  In another embodiment of the invention, the accumulator hydraulic pressure exerts work on the crankshaft via a variable displacement pump. The variable displacement pump is preferably replaced by a conventional electric starter motor used to start the engine.

  In yet another embodiment of the invention, the drive system further includes a fixed displacement pump having a constant pump fluid communication input from the sump and a constant pump fluid communication to the engine lubrication gallery for engine lubrication. have. The variable displacement pump preferably supplies only enough to compensate for the difference between the engine demand and the fixed displacement pump supply.

  In accordance with the present invention, engine auxiliary equipment requirements are combined with engine lubrication demands, and the variable displacement pump is adjusted based on the amount of fluid required by the engine lubrication system and the amount of fluid required by the engine accessory. As a result, fluid power can be provided immediately when required, and the efficiency of the entire engine lubrication system can be improved.

Embodiments of the present invention will be described below with reference to the accompanying drawings.
In FIG. 1, a variable displacement pump 6 and a variable displacement pump controller 20 are attached to the front cover 8 of the engine block 2. Note that the variable displacement pump 6 may be attached to another location near the engine block.

  An oil sump or an oil pan 4 is arranged below the engine block 2. Preferably, a high pressure manifold 18 is connected to the front cover 8 of the engine block 2.

  The variable displacement pump 6 is preferably driven by a common valve chain, gear or belt (not shown). The first fluid line 38 connects the variable displacement pump 6 to the oil pan 4.

  The second fluid line 40 connects the variable displacement pump 6 to the high pressure manifold 18 through the front cover 8 of the engine block 2. The high-pressure manifold 18 may be incorporated in the front cover 8, but may be completely separated from the front cover 8 and provided outside.

  The variable displacement pump 6 is adjusted by the variable displacement pump controller 20 based on the fluid or oil required by engine lubrication and the total amount of fluid required by the variable request engine accessories 10,14.

  The engine is preferably supplied with oil through a passage in the front cover, similar to a typical engine with a front mounted pump. The fluid line 42 supplies engine oil from the variable displacement pump 6 to the pressure regulator 44, and the other fluid line 46 supplies engine oil from the pressure regulator 44 to the engine lubrication gallery.

  The controller 20 receives an input from an engine control unit (ECU) 28. The ECU 28 monitors the temperature sensor 24, the engine speed sensor 26, and other sensors related to engine performance such as load sensors and vehicle speed sensors.

  The engine auxiliary machines 10 and 14 include, but are not limited to, the following. That is, a cooling fan driven by a hydraulic motor, an air conditioner (A / C) compressor, an engine coolant pump, an alternator, a supercharger, an electronic hydraulic valve drive system, a suspension actuator such as a pump or motor, and a power steering system.

  The amount of fluid in each of the auxiliary machines 10 and 14 is monitored by separate electronic pressure regulators 12 and 16. In the case of a power steering system, the power steering fluid pressure is preferably controlled by a modern power steering control valve.

  The return fluid from the engine accessory is supplied to the oil pan 4 or the oil gallery via the two fluid lines 32 and 36. Both fluid lines 32, 36 are preferably connected to the cooler 22, with one fluid line leading to the oil pan 4. Alternatively, the fluid lines 32 and 36 may be combined into one fluid line before entering the cooler 22.

  The pressure regulators 12 and 16 of the auxiliary machines 10 and 14 are connected to the high-pressure manifold 18 via the fluid lines 30 and 34, respectively, and use the high-pressure manifold 18 as a power source. Although the embodiment shown in FIG. 1 has two engine accessories, more engine accessories may be used without departing from the spirit of the present invention.

  Combining the requirements of engine accessories 10,14 with the requirements of engine lubrication and adjusting variable displacement pump 6 based on the amount of fluid required by the engine lubrication system and the amount of fluid required by engine accessories 10,14 Improves the overall system efficiency associated with the circuit by providing immediate fluid power when required.

  FIG. 2 illustrates the process of providing hydraulic pressure from the engine lubrication system for mechanical work. First, in step S1 in the figure, oil or fluid from the variable displacement pump 6 is supplied to lubricate the engine of one embodiment of the present invention.

  Next, in step S2, the variable displacement pump 6 supplies fluid or oil to at least one variable oil demand engine auxiliary machine 10,14. The variable displacement pump 6 is adjusted by a variable pump controller 20. Next, in step S3, pressure regulators 12 and 16 are provided to all engine auxiliary machines 10 and 14, respectively.

  Next, in step S4, the variable pump controller 20 determines the variable and continuous fluid required by the individual pressure regulators 12, 16 of the engine lubrication system and the variable request engine accessories 10, 14, regardless of the engine output. Based on the total amount, the temperature sensor and the speed sensor monitored by the ECU 28 are taken into account.

  In another embodiment of the present invention shown in FIG. 3, an accumulator 48 is connected to the high pressure manifold 18 via a fluid line 50. An accumulator control circuit is added to the ECU 28. The ECU controls whether the accumulator 48 is filled with working fluid, is stationary, or whether the working fluid is empty.

  In the mild hybrid embodiment, the accumulator 48 is sized to store a high pressure working fluid that is used to operate the hydraulic accessories 10,14. The accumulator 48 is filled during deceleration and braking and is supplied by the variable displacement pump 6.

  It should be noted that the accumulator 48 may be filled in other cases as long as it is used up by extended idling or engine start. The accumulator logic preferably attempts to maximize the fill level when the vehicle decelerates and to empty to a level of about 25-50% fill level during steady state driving.

  This tends to reduce some of the overall parasitic accessory load. In addition, the sub mode is to model the stop / start mode. In this case, when the vehicle is stopped by a signal, the A / C may still be operated.

  FIG. 4, which shows yet another embodiment of the present invention, shows a fully hybrid embodiment. The accumulator 48 is larger and can be selected to use the accumulated hydraulic energy to apply work to the crankshaft 52 via a hydraulic motor. The accumulator logic preferably seeks to maximize the fill during vehicle deceleration.

  The variable displacement pump 6 is preferably used as a hydraulic motor in this mode, and in practice is optionally replaced with a conventional electric starter motor. In other embodiments, the variable displacement pump 6 is used only as a pump, and the system includes a separate motor (not shown) to add work to the crankshaft 52.

  During the start event, if desired, a portion of the supply from accumulator 48 is used to pre-lubricate the engine. As in the case of the mild hybrid, the assistance by the hydraulic pressure is used to supply energy to the crankshaft 52 and to supply fluid to the auxiliary machine 10 during vehicle acceleration.

  In FIG. 5, which shows another embodiment of the present invention, the request system includes a fixed capacity oil pump 54, which is slightly large enough to supply energy. Is formed.

  A fluid line 56 connects the pump 54 to the pressure regulator 44. Another fluid line 58 connects the fixed displacement pump 54 to the oil pan 4. Accumulator 48 is preferably included in the requesting system.

  In this embodiment, the demand system only supplies sufficient oil to make up for the difference between the engine demand and the delivery of the fixed displacement pump 54. The fixed displacement pump is preferably sized optimally based on testing or modeling for the highest overall efficiency. This minimizes the inefficiency of squeezing all the lubricant that exits the high pressure circuit.

  Conditions that contribute to additional requirements include, but are not limited to: That is, driving additional engine oil demands such as variable valve timing (VVT) and variable valve drive (VVA) devices, oil injectors, and very fast engine operating conditions. The advantage of this embodiment is the possibility of higher overall efficiency by eliminating most of the oil squeeze loss at the expense of pump complexity.

  FIG. 6 is a flowchart illustrating the steps of providing hydraulic pressure for mechanical work from the engine lubrication system. First, in step S10 in the figure, oil or fluid from the variable displacement pump 6 is supplied to lubricate the engine of another embodiment of the present invention.

  Next, in step S11, the variable displacement pump 6 supplies fluid or oil to at least one variable oil demand engine auxiliary machine 10,14. Next, in step S12, pressure regulators 12 and 16 are provided to all engine accessories, respectively. The variable displacement pump 6 is adjusted by a variable pump controller 20.

  Next, in step S13, the variable pump controller 20 determines the variable and continuous fluid required by the individual pressure regulators 12, 16 of the engine lubrication system and variable request engine accessories 10, 14 regardless of engine output. Based on the total amount, the temperature sensor and the speed sensor monitored by the ECU 28 are taken into account.

  Next, in step S14, the variable displacement pump 6 supplies fluid or oil to the accumulator in order to store it as the accumulator hydraulic pressure for later use as mechanical work.

  It should be understood that the embodiments of the present invention described herein are merely exemplary, employing the principles of the present invention. References herein to details of the illustrated embodiments are not intended to limit the scope of the claims.

1 shows a schematic configuration of a system according to the present invention. 2 shows a flowchart of a process according to the invention. 1 shows a schematic configuration of a system including an accumulator according to an embodiment of the present invention. 3 shows a schematic configuration of a system including an accumulator according to another embodiment of the present invention. 6 shows a schematic configuration of a system including a fixed displacement pump according to still another embodiment of the present invention. 2 shows a flow chart of a process with an accumulator in one embodiment of the method according to the invention.

Explanation of symbols

6: Variable displacement pump 10, 14: Engine accessory 12, 16: Pressure regulator 48: Accumulator

Claims (19)

In an internal combustion engine, a method for providing hydraulic pressure from an engine lubrication system for mechanical work comprising:
a) supplying oil from a variable displacement pump to the engine lubrication gallery to lubricate the engine;
b) supplying oil from a variable displacement pump to at least one engine accessory having variable oil requirements and each having a pressure regulator;
c) adjusting the discharge of the variable displacement pump to the total amount of fluid required by the engine lubrication system and the fluid demand generated by the pressure regulator;
d) supplying oil from the variable displacement pump to the accumulator to accumulate accumulator hydraulic pressure for later use as mechanical work;
With a method. In claim 1,
At least one engine accessory
a) Cooling fan driven by hydraulic motor b) Power steering system c) Air conditioner compressor driven by hydraulic motor d) Engine coolant pump driven by hydraulic motor e) Alternator driven by hydraulic motor f) Supercharger driven by hydraulic motor g) Electrohydraulic valve drive system h) Selected from the group of suspension drive motors,
A method characterized by that. In claim 1,
The oil flow to lubricate the engine is based on engine parameters,
A method characterized by that. In claim 1,
Further comprising the step of using accumulator hydraulic pressure to operate at least one engine accessory;
A method characterized by that. In claim 1,
Further comprising using accumulator hydraulic pressure via a variable displacement pump to add work to the crankshaft driven by the engine;
A method characterized by that. In claim 1,
In order to lubricate the engine, it further comprises the step of supplying oil from the fixed displacement pump to the engine lubrication gallery, where the variable displacement pump is sufficient to compensate for the difference between the engine demand and the fixed displacement pump supply. Supplies as much oil as possible,
A method characterized by that. A hydraulic demand engine accessory drive system for an internal combustion engine comprising:
A variable displacement pump having a pump fluid communication input from an oil sump and a pump fluid communication output to a high pressure manifold;
A variable displacement pump controller attached to the variable displacement pump and communicating with the ECU;
An engine having an engine fluid communication input from the high pressure manifold and an engine fluid communication output to the oil sump;
Having a variable oil demand and pressure regulator, the pressure regulator comprising at least one engine accessory having a regulator input from the high pressure manifold and a regulator output to the sump;
The pump fluid communication output is regulated by the variable displacement pump controller based on the total amount of fluid required by the pressure regulator of at least one engine accessory, regardless of engine output.
A system characterized by that. In claim 7,
Further comprising an accumulator having a fluid communication line to a high pressure manifold for storing and supplying energy as accumulator hydraulic pressure;
A system characterized by that. In claim 8,
The ECU controls whether the accumulator receives oil, maintains oil, or supplies oil.
A system characterized by that. In claim 8,
The accumulator hydraulic pressure is operating at least one accessory,
A system characterized by that. In claim 8,
The accumulator hydraulic pressure is adding work to the engine driven crankshaft via the variable displacement pump,
A system characterized by that. In claim 11,
The variable displacement pump is replaced by an electric starter motor used to start the engine,
A system characterized by that. In claim 7,
The high pressure manifold is operating the pressure regulator,
A system characterized by that. In claim 7,
ECU monitoring engine sensor,
A system characterized by that. In claim 14,
Sensors monitor engine temperature and speed,
A system characterized by that. In claim 7,
At least one engine accessory
a) Cooling fan driven by hydraulic motor b) Power steering system c) Air conditioner compressor driven by hydraulic motor d) Engine coolant pump driven by hydraulic motor e) Alternator driven by hydraulic motor f) Supercharger driven by hydraulic motor g) Electrohydraulic valve drive system h) Selected from the group of suspension drive motors,
A system characterized by that. In claim 7,
At the regulator output to the oil sump of at least one engine accessory, further equipped with an oil cooler,
A system characterized by that. In claim 7,
A fixed displacement pump having a fixed pump fluid communication input from the sump and a fixed pump fluid communication output to an engine lubrication gallery for engine lubrication;
A system characterized by that. In claim 18,
The variable displacement pump supplies enough oil to compensate for the difference between the engine demand and the fixed displacement pump supply,
A system characterized by that.

Images